I have two nephews, fraternal twins, who are 16, and they're coming to visit for a few hours today. I've offered to teach them to how to sharpen a knife. They're into all things fiction-fantasy (Hobbitses, D&D, etc.), so they're excited about this. I'll show them the Gatco and Hapstone stuff, but I expect the focus to be on freehand sharpening. I'm not great at it, but I'm decent. Good enough to get them started, anyway.
Arkansas stones: free
Three paring knives: $3.81
Time with my nephews: priceless.
Arkansas stones: free
Three paring knives: $3.81
Time with my nephews: priceless.